Washington State has required investigation of all reported suspected pesticide related illnesses since 1970. While Washington has successfully initiated several effective interventions based on this data, the usefulness of the data for developing such interventions has been limited due to weaknesses of the data and of the data management system. Increasing the value of the information produced by Washington's occupational pesticide illness surveillance system must be based on a systematic evaluation and enhancement of data quality, data collection procedures, and data analysis and interpretation. The specific aim of this project is to increase the value of the information generated by the pesticide illness surveillance system as a means of formulating and evaluating more effective intervention efforts to protect workers from pesticide exposures and illnesses. Specifically this project will: 1) Evaluate and improve the quality of data collected by the surveillance system by assessing the quality of data produced by each of its components data sources, investigating the degree and determinants of underreporting through focus groups and a review of outpatient records, and development of a system for incorporating incident data into a Geographic Information System; 2) Improve the functionality and compatibility of the database management system by incorporating functions to analyze and export data using NIOSH variable definitions, coding and format; and 3) Enhance the analysis of the surveillance data and expand the dissemination of program and policy relevant information derived from surveillance data by gathering input from stakeholder on questions that need to be addressed, developing short focused reports on these topics, evaluating the usefulness of these reports, and institutionalizing those analyses and reports which generate information which directly helps to develop and evaluate intervention policies and programs.